Method for synchronizing seamless rate adaptation

Abstract

A DMT system and method with the capability to adapt the system bit rate on-line in a seamless manner. The DMT system provides a robust and fast protocol for completing this seamless rate adaptation. The DMT system also provides a framing and encoding method with reduced overhead compared to conventional DMT systems. The DMT system and method provide seamless rate adaptation with the provision of different power levels. This framing and encoding method enables a system with seamless rate adaptation capability. The system and method of the invention can be implemented in hardware, or alternatively in a combination of hardware and software.

What is claimed is:  
     
         1 . In a multicarrier transmission system including a transmitter and a receiver, the transmitter and receiver using a first bit allocation table to transmit a plurality of codewords at a first transmission bit rate, the plurality of codewords having a specified codeword size and including a specified number of parity bits for forward error correction, and a specified interleaving parameter for interleaving the plurality of codewords, a method for seamlessly changing a transmission bit rate comprising: 
 transmitting a message to change the transmission bit rate from the first transmission bit rate to a second transmission bit rate;    using a second bit allocation table at the receiver and at the transmitter for transmitting at the second transmission bit rate;    synchronizing use of the second bit allocation table between the transmitter and receiver; and    transmitting codewords at the second transmission bit rate using the same specified interleaving parameter, specified codeword size, and specified number of parity bits for forward error correction that are used to transmit codewords at the first transmission bit rate to achieve a seamless change in transmission bit rate.